The present invention relates to a method of and an arrangement for exchanging tool holders in a working unit for working of workpieces, in accordance with which a tool holder is removed from a working position and exchanged by another tool holder.
It is known to design a tool holder as a polygonal receiving body with exchangeable units. This polygonal receiving body has at its lateral limiting faces a plurality of tool holders for receiving of tools. The receiving body is cyclically rotatable about a central axis so as to bring the respective tool holder to working position.
The disadvantage of this method and arrangement is that for bringing another receiving body with other tool holders to working position, the entire large, heavy and complicated receiving body with the tool holders must be dismounted from the working machine, transported back and deposited in a collector, thereafter another receiving body with tool holders must be transported to the working machine and mounted therein. Therefore, the entire mass of the receiving body with all tool holders must be transported back, when it is necessary to exchange the same by another receiving body with tool holders. The fitting period or dead time in this system is therefore relatively high.
Finally, the number of the tool holders mounted on the same receiving body, such as for example drilling heads, is structurally limited. Structurally, the receiving body must be placed with high accuracy in the working machine so that those tool holders which are located not in the working position must be positioned with high accuracy, which is also disadvantageous.